﻿/* ==============================================================================
*
*   Copyright (c) 2010, Pierre Favier
*   All rights reserved.
*
*   NTasking is free software: you can redistribute it and/or modify it
*   under the terms of the GNU General Public License as published by the
*   Free Software Foundation.
*
*   Redistribution and use in source and binary forms, with or without
*   modification, are permitted provided that the following conditions
*   are met:
*
*   -   Redistributions of source code must retain the above copyright notice,
*       this list of conditions and the following disclaimer.
*
*   -   Redistributions in binary form must reproduce the above
*       copyright notice, this list of conditions and the following
*       disclaimer in the documentation and/or other materials
*       provided with the distribution.
*
*   THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
*   WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
*   OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
*   DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
*   BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
*   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
*   TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
*   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
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*   THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
*   SUCH DAMAGE.
*
* ============================================================================== */

using NTasking;
using NTaskingQuickStart.Logging;

namespace NTaskingQuickStart.Printing
{

    internal class JobHandler : Task
    {
        private const double WarmupTime = 5.0;
        private const double HibernateTime = 1.0;
        private const double ShutdownTime = 10.0;
        private const double PrintTime = 1.0;
        private const double HibernateTimeout = 30.0;
        
        private readonly JobSpooler _spooler;
        private bool _hibernating = true;
        
        
        internal JobHandler(JobSpooler spooler)
        {
            _spooler = spooler;
        }
        
        
        protected override void Body()
        {
            bool shutdown = false;
            
            while (!shutdown)
            {
                if (_hibernating)
                    shutdown = HandleJob(_spooler.NextJob());
                else
                    Ada.Select(s => s.
                        Call(_spooler.NextJob)().
                        Then(job => shutdown = HandleJob(job)).
                    OrDelay(HibernateTimeout).
                        // If no print job received after 30 seconds, put the
                        // printer in hibernation
                        Then(StartHibernation));
            }
           
            // Simulate printer shutdown
            Ada.Delay(ShutdownTime);
           
            Logger.WriteLine("Printer has been turned off");
        }
        
        
        private bool HandleJob(PrintJob job)
        {
            if (job == null)
                return true;
            
            if (_hibernating)
                EndHibernation();
            
            // Simulate the printing here
            Logger.WriteLine("Printing " + job.File);
            Ada.Delay(PrintTime);
            
            _spooler.DonePrinting(job.ID, PrintStatus.Success);
            
            return false;
        }
        
        
        private void StartHibernation()
        {
            _hibernating = true;
            
            // Simulate putting the printer in hibernation
            Logger.WriteLine("Printer is going into hibernation");
            Ada.Delay (HibernateTime);
        }
        
        
        private void EndHibernation()
        {
            _hibernating = false;
            
            // Simulate printer warm-up
            Logger.WriteLine("Printer is warming up");
            Ada.Delay (WarmupTime);
        }

    }

}